AISI Type M6 High Speed Tool Steel Sheet,Plate

AISI Type M6 High Speed Tool Steel Sheet/Plate Product Information -:- For detailed product information, please contact sales. -: AISI Type M6 High Speed Tool Steel Sheet/Plate Synonyms -:- For detailed product information, please contact sales. -:

AISI Type M6 High Speed Tool Steel Product Information -:- For detailed product information, please contact sales. -: # **Product Introduction: AISI Type M6 High-Speed Tool Steel (UNS T11306)** ## **Overview** **AISI M6 (UNS T11306)** is a **high-carbon, ultra-high vanadium, cobalt-enriched molybdenum high-speed steel** that represents one of the **most wear-resistant grades** in the conventional HSS family. Occupying the extreme end of the wear-resistance spectrum, M6 is engineered for machining the most abrasive materials where tool life is limited by severe wear rather than thermal softening. Its formulation delivers an unparalleled combination of **extreme hardness and abrasion resistance** at the expense of toughness and grindability, making it a specialized solution for targeted applications. ## **1. Chemical Composition (Nominal %)** | Element | Content (%) | Primary Function | |---------|------------|------------------| | **Carbon (C)** | 0.75 - 0.85 | Provides matrix hardness and combines with vanadium to form massive carbide volume. | | **Tungsten (W)** | 3.75 - 4.50 | Contributes to hot hardness and secondary hardening. | | **Molybdenum (Mo)** | 4.50 - 5.50 | Primary hardening element; ensures deep hardenability and grain refinement. | | **Chromium (Cr)** | 3.75 - 4.50 | Enhances hardenability and provides oxidation resistance. | | **Vanadium (V)** | **4.50 - 5.50** | **Ultra-high content.** Forms an extremely high volume of hard vanadium carbides (VC), providing supreme abrasion resistance. | | **Cobalt (Co)** | **11.00 - 13.00** | **Very high content.** Dramatically elevates red-hardness and tempering resistance by solid solution strengthening of the matrix. | | **Silicon (Si)** | 0.15 - 0.40 | Deoxidizer. | | **Manganese (Mn)** | 0.15 - 0.40 | Improves hardenability. | | **Sulfur (S)** | ≤ 0.03 | Residual element. | | **Phosphorus (P)** | ≤ 0.03 | Residual element. | | **Iron (Fe)** | Balance | Base metal. | **Key Chemistry Note:** M6's identity is defined by its **two extreme alloying features: ultra-high vanadium (V) and very high cobalt (Co)**. This creates a microstructure densely packed with hard vanadium carbides, supported by a cobalt-strengthened matrix. The **carbon content is moderate** to balance carbide formation without excessive brittleness, but the overall composition pushes the limits of conventional HSS metallurgy. ## **2. Physical & Mechanical Properties** | Property | Typical Value / Condition | |----------|--------------------------| | **Density** | ~8.3 g/cm³ (0.300 lb/in³) | | **Melting Point** | ~1400°C (2550°F) | | **Thermal Conductivity** | Low (~25 W/m·K at 20°C) | | **Coefficient of Thermal Expansion** | ~11.0 × 10⁻⁶/K (20-500°C) | | **Modulus of Elasticity** | ~205 GPa (29.7 × 10⁶ psi) | | **Annealed Hardness** | 265-311 HB | | **Hardened & Tempered Hardness** | **65-68 HRC** (Can achieve 66-68 HRC with proper heat treatment). | | **Red Hardness** | **Exceptional.** Maintains cutting edge hardness at very high temperatures, superior to most HSS except for grades like M41/42/46. | | **Abrasion Resistance** | **Extreme.** Arguably the highest among standard AISI M-series HSS grades due to the massive volume of vanadium carbides. | | **Toughness** | **Very Low.** The high volume of hard, brittle carbides and the cobalt-strengthened matrix significantly reduce impact resistance. Suitable only for stable, shock-free cutting conditions. | | **Tempering Temperature** | 540-600°C (1000-1110°F), **triple tempering is mandatory**. | | **Grindability** | **Exceptionally Poor** (Approx. 15-20% of M2). One of the most difficult steels to grind. | ## **3. International Standards & Cross-References** | Standard | Designation | Notes | |----------|------------|-------| | **UNS** | T11306 | | | **AISI/ASTM (USA)** | M6 (ASTM A600) | | | **ISO (International)** | **HS 3-4-2-12** (ISO 4957) | Closest equivalent. | | **DIN (Germany)** | **~1.3247** | Approximate functional equivalent. | | **JIS (Japan)** | No direct equivalent. | | | **GB (China)** | **W4Mo3Cr4V5Co12** | Approximate composition. | | **Common Name** | **"Super Cobalt High Vanadium HSS"** | Descriptive industry term. | ## **4. Product Applications** M6 is a **specialist grade** reserved for applications where abrasive wear is the primary failure mechanism and cutting forces are stable. ### **Primary Cutting Applications:** * **Machining Highly Abrasive Materials:** * **Fiber-Reinforced Plastics (FRP):** Carbon fiber, fiberglass composites. * **Abrasive Non-Ferrous Alloys:** High-silicon aluminum (e.g., AlSi alloys for pistons), metal matrix composites (MMCs), nickel-based superalloys in finishing operations. * **Hardened Steels:** Finishing cuts on tool steels and hardened components. * **Specific Tool Types:** * **Solid carbide alternative:** **End mills, drills, and reamers** for the above materials where HSS toughness is an advantage over solid carbide. * **Broaches and gear hobs** for long production runs on abrasive materials. * **Form tools and inserts** (often as brazed tips) for turning and milling. ### **Non-Cutting Wear Applications:** * **Cold work tooling** for forming abrasive materials (e.g., powder compaction punches). * **Wear parts** in severe abrasive environments, such as guides, nozzles, and slats. ### **Performance Context:** M6 is selected **not for general-purpose machining, but as a problem-solver for specific, severe wear problems.** Its use is justified when tools made from grades like M2, M4, or even M42 wear out too quickly in abrasive conditions, and the application cannot tolerate the brittleness of carbide. ## **5. Processing & Heat Treatment Guidelines** **Processing M6 requires expertise and specialized equipment due to its high alloy content.** ### **Forging:** * Heat slowly and uniformly to **1080-1130°C (1975-2065°F)**. * **Do not forge below 950°C (1740°F).** * Cool **very slowly** in an insulating medium or furnace immediately after forging to prevent cracking. ### **Annealing:** * Heat to **870-900°C (1600-1650°F)**, hold, then furnace cool very slowly (≤10°C/hour to 500°C). * Expected annealed hardness: 265-311 HB. ### **Hardening (Critical):** 1. **Preheat:** **Two-stage preheating is essential:** 550-600°C (1020-1110°F) and then 850-900°C (1560-1650°F). 2. **Austenitize:** **1170-1200°C (2140-2190°F).** Precise temperature control is vital to dissolve sufficient carbides without causing grain growth. 3. **Quench:** In salt bath, vacuum furnace with high-pressure gas (N₂/Ar), or oil for simple shapes. ### **Tempering (Most Critical Step):** * **Temper immediately** upon reaching hand-warm temperature (40-50°C). * **Triple temper at 540-560°C (1005-1040°F)** for 2+ hours each cycle. A fourth temper may be beneficial. * **Cryogenic treatment** (e.g., -80°C to -196°C) between tempers is highly recommended to maximize transformation of retained austenite and achieve ultimate hardness and dimensional stability. ## **6. Machinability & Grindability** * **Machinability (Annealed):** **Very Poor** (~30% of M2). Requires rigid setups, positive rake tools, low speeds/feeds, and ample coolant. * **Grindability:** **Extremely Poor.** This is the major drawback of M6. * **Wheel Selection: Diamond or CBN (Cubic Boron Nitride) wheels are essentially mandatory** for efficient grinding. * **Technique:** Use light infeeds, high wheel speeds, and copious coolant to avoid thermal damage (grinding burns) which can cause micro-cracks. --- **Disclaimer:** AISI M6 is a highly specialized, difficult-to-process premium tool steel. Its successful implementation requires extensive metallurgical knowledge, precise heat treatment facilities, and careful application engineering. The information provided is for reference only. Always consult the material producer's certified technical data sheets and engage qualified specialists for heat treatment and tool design. Performance will vary based on manufacturing quality (e.g., ESR/VAR remelting is common for M6) and exact processing parameters. -:- For detailed product information, please contact sales. -: AISI Type M6 High Speed Tool Steel Specification Dimensions Size： Diameter 20-1000 mm Length <6737 mm Size:We can customized as required Standard： Per your request or drawing We can customized as required Properties（Theoretical） Chemical Composition -:- For detailed product information, please contact sales. -: AISI Type M6 High Speed Tool Steel Properties -:- For detailed product information, please contact sales. -:

Applications of AISI Type M6 High Speed Tool Steel Sheet,Plate -:- For detailed product information, please contact sales. -: Chemical Identifiers AISI Type M6 High Speed Tool Steel Sheet,Plate -:- For detailed product information, please contact sales. -:

Packing of AISI Type M6 High Speed Tool Steel Sheet/Plate -:- For detailed product information, please contact sales. -: Standard Packing: -:- For detailed product information, please contact sales. -: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and Steel Sheet/Plate drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 3208 gallon liquid totes Special package is available on request. E FORUs’ is carefully handled to minimize damage during storage and transportation and to preserve the quality of our products in their original condition